When it was announced that the new Shelby GT350 would forgo the familiar Tremec TR-6060 transmission in favor of a new gearbox, our interests were piqued. The familiar 6060 six-speed manual has proven a robust, reliable gearbox for the big-power brute that is the Shelby GT500—and even more so in aftermarket Magnum trim. However, the new Shelby is a different animal. It trades brute force for high-rpm corner carving, and reducing weight was a prime directive for the Ford Performance engineers.

Shedding weight was clearly a primary focus for Ford Performance engineers designing the new Shelby GT350. One way they reduced weight was choosing a new, lighter six-speed manual transmission that would live behind its high-revving, 500-plus-horsepower 5.2-liter engine. Those ribs in the case are carefully designed to add the necessary strength without packing on the pounds.

“Unless you are going to build a carbon-fiber-tubbed car there aren’t a lot of weight savings silver bullets,” Jamal Hameedi told us at last’s Los Angeles International Auto Show. “In order to get weight out or to offset weight add (from bigger brakes, wheels, and tires), it’s really about attention to detail and shaving a kilogram or a pound here and half a kilogram there. So we tried to have that philosophy on every new part we touched.”

Naturally, that philosophy trickled down to what transmission would fill the tunnel of the new GT350.

“The transmission, for sure, isn’t as stout as a 6060. This has got a dual-mass flywheel, which does ease the shock loads going into the trans,” he explained. “We never even thought of putting a 6060 in because they are way too heavy.”

We had the opportunity to examine one of the transmissions that Ford used in its durability prove-out for the new Shelby. It was sent back to Tremec for a teardown and evaluation after enduring four 24-hour all-out racetrack sessions, and it passed with flying colors. Another TR-3160 that underwent durability testing just for the transmission came back and it looked brand-new inside. Many factors—case design, center-to-center distance, materials, number of input shaft splines, and more—come into play when calculating a torque capacity for a transmission, but in OE applications they are built to take what the stock engine delivers. In the case of the Shelby GT350’s TR-3160 transmission is rated for up to 425 lb-ft of torque.

The transmission chosen for the latest top-shelf Mustang is the Tremec TR-3160 six-speed manual. It is a new transmission to the Mustang world, but it isn’t a new design. In fact, this transmission began development with the advent of the S197 Mustangs, though due to its sophisticated—and thus costly—nature never made it into an OE program until recently. However, during that time, this transmission has benefitted from what Tremec has learned from many other products, including the vaunted TR-6060.

“The TR-3160 benefits from nearly every trick in the Tremec playbook—taking cues not only from several of our own successful products, but also what we feel are some of the best practices of the industry as a whole,” Tremec’s Enthusiast Marketing Director Nate Tovey explained. “In terms of technology density, it is arguably the most advanced manual transmission the segment has ever seen.”

If you want a look at how Tremec executes that playbook, this video delves into the company’s manufacturing process…

By putting the best design elements from its other products into the 3160, the transmission offers some great benefits to drivers of a high-performance Mustang. Carrying a 425 lb-ft torque capacity rating, the TR-3160 is geared to take advantage of the Shelby’s powerband with the following ratios: First: 3.253:1, Second: 2:233:1, Third: 1.611:1, Fourth: 1.24:3, Fifth 1:1, Sixth: .629:1, and Reverse: 2.955:1.

Placed side-by-side, you can see the reduced mass of the 3160 gear (left). The TR-3160 was built to be light, efficient, and quiet, while still holding up to everything a flat-plane-crank 5.2-liter can throw at it.

“Like a GT350 next to a GT500, the TR-3160 is like a surgical instrument next to a sledgehammer when compared to the TR-6060. Though what the 3160 gives up in size and torque capacity, it makes up for in weight savings and high-rpm shiftability.” Nate said. “It uses a ‘6060-esque’ synchro package that, in conjunction with its reduced internal mass, translates into a significant gain in synchronizer capacity. It also employs a multi-rail shift mechanism that allows for a more compact design and optimized placement of the shift forks for an improved shift feel.”

The feel of the shifting is said to be sporty, which makes a lot of sense when the 3160 is paired with the high-revving Voodoo engine in the new Shelby.

The TR-3160 and 6060 synchronizers are not exactly interchangeable. While the TR-3160 utilizes the same synchronizer platform carried over from TR-6060, its materials are tailored for this application.

“The TR-3160 is an ideal pairing with the new GT350 because it takes a similar approach to performance—trading out some of the old-school muscle-car savagery for world-class sophistication,” Nate added. “From front to back, this is a much different car than any Mustang we’ve seen before, yet its heritage remains proudly intact. We’ve worked hard to accomplish the same with our new transmission and are proud to be part of the GT350 program.”

What’s even better is that we may eventually see an aftermarket variation of this gearbox from Tremec.

Like its bigger TR-6060 cousin, the Tremec 3160 utilizes triple-cone synchronizers on the First and Second gears, while the remaining gears use double-cone synchros. The job of a synchro in a trans is to adjust the speed of the gears by slowing them down or speeding them up so they are matched enough for the shift to take place smoothly. A multi-cone unit is advantageous because it essentially packs more surface area and torque capacity into the same space as a single synchro. The concept is similar to that of using a dual-disc clutch.

“It’s too soon to tell, but yes, the conversation has taken place more than once. Several of us here at Tremec can’t look at a product like the TR-3160 without viewing it through a ‘performance aftermarket prism,’” Nate said. “Whether or not it passes the feasibility stage remains to be seen, but you can bet that we are going to find out!”

Naturally, we couldn’t wait to get a look inside this new gearbox to see what kind of gears we’ll be rowing in the future. So, we took the opportunity to stop by the Tremec offices in Michigan to peek inside one of the TR-3160 prototypes that had run in one of the Shelby GT350 test cars on the racetrack. Since you are an SVTP Front Page reader, you get to look over our shoulders and into the new Tremec TR-3160 transmission…

One way Tremec reduced mass inside the 3160 is by utilizing rifle-drilled gear shafts. This process gives up little in the way of strength, but reduces rotating mass for greater efficiency. It also helps reduce overall transmission weight.As you are likely aware, the Track Pack-equipped GT350 and the GT350 R are fitted with an external transmission cooler for additional cooling at the race track. The cooler is fed by this integral pump, which is driven by the front cluster. It pumps about 3 gallons per minute, which is sufficient for cooling, but not enough to introduce a lot of parasitic loss in the transmission.The output fitting of the pump is cast right into the transmission. Interestingly, Shelby GT350s that aren’t optioned with the oil cooler with get a different transmission that does not feature the plumbing for the transmission cooler.These linear bearings side into the case, they allow for low-friction shifting, which is smooth and efficient.At the rear of the 3160 housing is the return fitting for the transmission cooler. To its left is the speed sensor and below it a transmission temperature sensor. That sensor is just threaded into the side of the transmission. It does not touch fluid, so if you need to swap it out, you won’t spill any lube.As you know from our prior coverage of the Shelby GT350’s 5.2-liter engine, while it may not have the brutal grunt of the supercharged Trinity engine, its flat-plane crank design offers some serious high-rpm goodness. As such, Tremec engineers opted to use GT500-style output splines and a simple flat flange (left) for adaptation to the driveshaft.Here is your first look at the remote shifter used in the Shelby GT350. It looks rather robust. We can’t wait to feel how it performs atop the TR-3160 in this new application. If, however, Tremec ever decides to release an aftermarket version of this trans, you can rest assured it will have a direct-shift setup. Tremec TR-3160 Powerflow Gallery

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Maybe I fail at reading, but they are using a transmision that can only support 425lb/ft tq? Seems kinda low for a high rev'ing v8 that you know someone is going to boost. But then again I guess that's what the aftermarket is for if you're adding that kind of power.

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Maybe I fail at reading, but they are using a transmision that can only support 425lb/ft tq? Seems kinda low for a high rev'ing v8 that you know someone is going to boost. But then again I guess that's what the aftermarket is for if you're adding that kind of power.

There's more to it than just a rating. What about GVWR capacity? The MT82 is rated for 383 lb ft but for a vehicle that has a total GVWR of 5000 kilograms. The Camaro TR6060 has the M 10 version rated for 410 lb ft for a dry weight vehicle at 3820 lbs.

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There's more to it than just a rating. What about GVWR capacity? The MT82 is rated for 383 lb ft but for a vehicle that has a total GVWR of 5000 kilograms. The Camaro TR6060 has the M 10 version rated for 410 lb ft for a dry weight vehicle at 3820 lbs.

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I hope that tranny is smooth shifting at 8500 rpm as that will be the secret.

Exactly. I'm not so worried about capacities so much as how are those gears and especially the syncros going to hold up to an 8100 RPM redline...and beyond. This engine isn't going to be about who can get the most power out of it but who dares to spin it so fast it creates its own gravitational field.